2016-03-11 16:05 GMT+03:00 Alexander Potapenko <[email protected]>:
> On Fri, Mar 11, 2016 at 12:47 PM, Andrey Ryabinin
> <[email protected]> wrote:
>> 2016-03-09 14:05 GMT+03:00 Alexander Potapenko <[email protected]>:
>>
>>> +struct kasan_track {
>>> + u64 cpu : 6; /* for NR_CPUS = 64 */
>>
>> What about NR_CPUS > 64 ?
> After a discussion with Dmitry we've decided to drop |cpu| and |when|
> at all, as they do not actually help debugging.
> This way we'll make kasan_track only 8 bytes (4 bytes for PID, 4 bytes
> for stack handle).
> Then the meta structures will be smaller and have nice alignment:
>
Sounds good.
> struct kasan_track {
> u32 pid;
> depot_stack_handle_t stack;
> };
>
> struct kasan_alloc_meta {
> struct kasan_track track;
> u32 state : 2; /* enum kasan_state */
> u32 alloc_size : 30;
> u32 reserved; /* we can use it to store an additional stack
> handle, e.g. for debugging RCU */
> };
>
> struct kasan_free_meta {
> /* This field is used while the object is in the quarantine.
> * Otherwise it might be used for the allocator freelist.
> */
> void **quarantine_link;
> struct kasan_track track;
> };
>
>
>>> + u64 pid : 16; /* 65536 processes */
>>> + u64 when : 42; /* ~140 years */
>>> +};
>>> +
>
>
>
> --
> Alexander Potapenko
> Software Engineer
>
> Google Germany GmbH
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